feat: implement FlowExecutor for executing flow definitions with DAG traversal and node execution

ccw/frontend/src/lib/utils.ts

@@ -0,0 +1,17 @@
+import { type ClassValue, clsx } from "clsx";
+import { twMerge } from "tailwind-merge";
+
+/**
+ * Merges class names using clsx and tailwind-merge.
+ * This utility combines Tailwind CSS classes intelligently,
+ * handling conflicts and deduplication.
+ *
+ * @example
+ * cn("px-2 py-1", "px-4") // => "py-1 px-4"
+ * cn("bg-primary", condition && "bg-secondary") // conditional classes
+ */
+export function cn(...inputs: ClassValue[]): string {
+  return twMerge(clsx(inputs));
+}
+
+export type { ClassValue };